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Denise Lego Markus Plaumann Thomas Trantzschel Joachim Bargon Henning Scheich Gerd Buntkowsky Torsten Gutmann Grit Sauer Johannes Bernarding Ute Bommerich 《NMR in biomedicine》2014,27(7):810-816
Parahydrogen‐induced polarization (PHIP) is a promising new tool for medical applications of MR, including MRI. The PHIP technique can be used to transfer high non‐Boltzmann polarization, derived from parahydrogen, to isotopes with a low natural abundance or low gyromagnetic ratio (e.g. 13C), thus improving the signal‐to‐noise ratio by several orders of magnitude. A few molecules acting as metabolic sensors have already been hyperpolarized with PHIP, but the direct hyperpolarization of drugs used to treat neurological disorders has not been accomplished until now. Here, we report on the first successful hyperpolarization of valproate (valproic acid, VPA), an important and commonly used antiepileptic drug. Hyperpolarization was confirmed by detecting the corresponding signal patterns in the 1H NMR spectrum. To identify the optimal experimental conditions for the conversion of an appropriate VPA precursor, structurally related molecules with different side chains were analyzed in different solvents using various catalytic systems. The presented results include hyperpolarized 13C NMR spectra and proton images of related systems, confirming their applicability for MR studies. PHIP‐based polarization enhancement may provide a new MR technique to monitor the spatial distribution of valproate in brain tissue and to analyze metabolic pathways after valproate administration. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Evelyn E. Nash Tara C. Henning Cau D. Pham Kevin Pettus Samera Sharpe Ellen N. Kersh 《Diagnostic microbiology and infectious disease》2019,93(4):369-371
Neisseria gonorrhoeae quickly develops drug resistance. Time-kill curves revealed that EDTA and TOL-463 inhibit growth similar to penicillin, ciprofloxacin, and azithromycin. Furthermore, synergistic and additive antimicrobial interactions occurred when EDTA and TOL-463 were combined with penicillin or azithromycin, respectively, suggesting that further investigations into these unconventional antimicrobials may be advantageous. 相似文献
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Thom S. Lysen Hazel I. Zonneveld Ryan L. Muetzel M. Arfan Ikram Annemarie I. Luik Meike W. Vernooij Henning Tiemeier 《Journal of sleep research》2020,29(5)
Sleep problems increase with ageing. Increasing evidence suggests that sleep problems are not only a consequence of age‐related processes, but may independently contribute to developing vascular or neurodegenerative brain disease. Yet, it remains unclear what mechanisms underlie the impact sleep problems may have on brain health in the general middle‐aged and elderly population. Here, we studied sleep's relation to brain functioning in 621 participants (median age 62 years, 55% women) from the population‐based Rotterdam Study. We investigated cross‐sectional associations of polysomnographic and subjectively measured aspects of sleep with intrinsic neural activity measured with resting‐state functional magnetic resonance imaging on a different day. We investigated both functional connectivity between regions and brain activity (blood‐oxygen‐level‐dependent signal amplitude) within regions, hierarchically towards smaller topographical levels. We found that longer polysomnographic total sleep time is associated with lower blood‐oxygen‐level‐dependent signal amplitude in (pre)frontal regions. No objective or subjective sleep parameters were associated with functional connectivity between or within resting‐state networks. The findings may indicate a pathway through which sleep, in a ‘real‐life’ population setting, impacts brain activity or regional brain activity determines total sleep time. 相似文献
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Tor S. Clemmensen M.D. Henning Mølgaard M.D. D.M.Sc. Niels F. Andersen M.D. Ph.D. Steen Baerentzen M.D. Jens Soerensen M.D. D.M.Sc. Steen H. Poulsen M.D. D.M.Sc. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(11):1777-1780
The present case illustrates the diagnostic challenges in symptomatic patients with heart failure of unknown etiology. The patients were previously diagnosed with κ‐light chain amyloidosis without cardiac involvement. Echocardiography showed heart failure with mildly reduced ejection fraction but no signs of amyloidosis. Coronary angiogram showed normal arteries and 11C‐PIB positron emission tomography was negative for amyloid deposits. Exercise testing revealed severe heart failure and reduced coronary flow velocity reserve. Endomyocardial biopsies showed amyloid in the intramural coronary arteries without interstitial amyloid deposits. Hence, the patient was diagnosed with microvascular dysfunction‐induced heart failure due to vessel wall amyloidosis. 相似文献
88.
Henning Burmeister Stefan Aebi Cristina Studer Martin F. Fey Oliver Gautschi 《Supportive care in cancer》2012,20(1):141-147
Background
We assessed adherence to the European Society of Medical Oncology (ESMO)/Multinational Association of Supportive Care in Cancer recommendations for prophylaxis of chemotherapy-induced nausea and vomiting (CINV) at our institution. 相似文献89.
An 8‐year‐old girl showed psoriatic lesions confined to her autoamputated left thigh. She was wearing an above‐the‐knee prosthesis that induced plaque psoriasis by koebnerization. Rapid clinical remission was achieved using tacrolimus 0.03% ointment. 相似文献
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